For about $8 you can buy 1,500 ladybugs. Since August, I have released 7,500 in my yard.
Despite all of the troubles I’ve had getting things rolling in the garden this year, I have avoided dousing my edibles in chemicals to ward off or kill the pests. It’s felt like a Pyrrhic victory, at times. Sure, maybe a little chemical deterrent would have boosted my harvest and put more food on the table, but if I want fruits and vegetables that have been repeatedly sprayed with deadly herbicides and pesticides, I can always go to the supermarket. The chemicals individuals apply to their household pest problems wash into the soil with watering, and wash into the water table, rivers, and ocean with the rains just as easily as those used by industrial farming operations.
An alternative to the chemical route is bio-control — applying the checks and balances that exist in nature to agriculture. The plants, animals, and fungi commonly referred to as “pests” are often essential components of local ecology that have simply gotten out of balance. They become pests when there are more of them than there should be. Nature always balances, but not always on our schedule and not always in time to save the crop (one way of balancing is the over-sized population eats all of the crop, then starves or disperses).
I have a heavy infestation of aphids on half of my remaining squash. I haven’t mentioned this last bunch of out-of-season squash because I didn’t want to jinx it (as if jinxing could explain all of my issues), but I have hope for my Delicata. The failed Butternut, Pink Banana, and Acorn varieties suffered from similar infestations of aphids, and I had some success with the four packages of ladybugs I released then, though they didn’t stick around as well as they have this time.
The aphid population went from a few hundred to a few hundreds of thousands in a week’s time. Typically they’re kept in check by a variety of predators and diseases, and if left alone their numbers will eventually attract the things that feed on them. A few ladybugs and lacewings had already arrived when I took my $8 to market. But seeing as how aphids reproduce asexually, skip the egg-laying stage, and go right to live birth at the rate of 12 offspring per aphid per day, I thought a massive influx of predators couldn’t hurt.
A natural enemy of the aphid is the ladybug. Despite its unassuming North American name (in Iran it is called the Shoe Cobbler, and in Finland, the Blood Gertrud), the ladybug is a voracious insectivore that devours as many as 50 aphids a day. These beneficial beetles reproduce quickly, though not as efficiently or as voluminously as their prey (to be expected). Yet, even in its several larval stages the ladybug feasts. In some ways the immature ladybug benefits the eradication effort more than the adult in that it is flightless and less apt to wander off. Introduced predators are under no obligation to accomplish anything on your behalf, much like Congress or bailed-out financial institutions.
And you can hardly tether the little bugs in place. But, if there’s plenty of prey and somewhere for them to hide when things get tough, then they tend to hang around for longer.
Of the 450 species of ladybugs in North America, the most common commercially available type is the Convergent Lady Beetle. The natural habitat for this beetle ranges from Canada to South America, so it’s native, but large infusions of this particular species can disrupt local populations of unique regional ladybugs. When buying ladybugs for bio-control, be sure they are pre-fed. Since they are often collected while hibernating in massive colonies, if they haven’t eaten, they cannot ignore their instinct to disperse, and they will fly — even from aphid-infested plants — before feeding.
I deployed my recent surge of bugs five days ago. By day two at least half had deserted. Today there are still a few hundred willing to eat and mate with abandon. They’re doing a heck of a job, but something tells me there are 1,500 more ladybugs with my name on them at the nursery.
I like hearing about garden reality. Our native ladybugs have been largely superseded by the Asian types which are sort of pesky. In the last couple years it has been the Japanese beetle that devastates everything here.
A saw a lady bug in my garden this morning when I was watering!! Yay!
I never thought about it in terms of overriding native ladybugs, thanks for that, now I’m an even more obnoxious environmentalist. Not even ladybugs are sacred.
next ladybug season you can have some of ours. the empty lot by our house was swarming with them earlier in the year. they were literally carpeting the ground. which I found odd because there were only very few and very tiny little weeds for them to hang out on and I couldn’t find any aphids. crazy ladybugs.
I think next season we’ll get some ladybugs as well. Hope that there’s no jinx from this post
[...] last few weeks of that time they sat on plants sickened first by a massive aphid infestation (see Convergent lady killers, posted Nov. 17) and then by powdery mildew — the same pest that kept all the other out-of-season [...]
I had the same scenario in my garden earlier this year, only the aphids were on my cantaloupe, and then the sooty mold came. On the plus side, the cantaloupe (doomed to fail anyway because I learned the hard way that store-bought cantaloupes are typically hybrids that won’t produce edible cantaloupes) became my trap plant, and the aphids all stayed there and left the rest of my garden mostly alone. The ladybugs are fun to release on them (release the hounds!) — just make sure you’re not buying the invasive Asian ladybeetle kind (they have a sort of “M” pattern on their head — not only will they invade your house, but they bite).